/*
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at 
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *  
 */

namespace org.apache.commons.collections
{

    /**
     * Marker interface for collections, maps and iterators that are unmodifiable.
     * <p>
     * This interface enables testing such as:
     * <pre>
     * if (coll is Unmodifiable) {
     *   coll = new ArrayList(coll);
     * }
     * // now we know coll is modifiable
     * </pre>
     * Of course all this only works if you use the Unmodifiable classes defined
     * in this library. If you use the JDK unmodifiable class via java util Collections
     * then the interface won't be there.
     *  
     * @since Commons Collections 3.0
     * @version $Revision: 7130 $ $Date: 2011-06-04 20:48:14 +0200 (Sa, 04. Jun 2011) $
     *
     * @author Stephen Colebourne
     */
    public interface Unmodifiable
    {
        // marker interface - no methods to implement
    }
}